>Every physical thing has a name. Every piece of code and class should be treated like a physical thing. That is IMO the essence of object oriented programming.

<cheapshot>Especially abstract classes</cheapshot> <g>

>If I fill a room with toys without sorting them that is clutter. If there is only one ball, you can find it with lots of digging. If the things are sorted alphabetically and arranged on the walls you can find it faster.

Since vfp works single inheritance, based on the above I'ld argue at least to keep some (lower/last) childclasses in one classlib/file with a rather specific common ancestor. Something like

define class cProjTxtBox as cBaseTxtBox 
  define class cProjNumTxtBox as cProjTxtBox 
    define class cProjYearTxtBox as cProjNumTxtBox 
  define class ... as cProjTxtBox 

regards

thomas